1. Field of the Invention
This invention relates to electronic business machines that provide a printed readout, and more particularly to a low silhouette paper feeding mechanism for advancing paper past the printing station of an electronic business machine.
2. Description of the Prior Art
With the advent of the MOS/LSI circuit technique, many types of electronic business machines have become widely available to the public. For example, electronic calculators have been priced within the reach of practically everyone. For the most part, such electronic calculators employ a visual display, such as, a liquid crystal display or a light-emitting diode display. However, these displays are generally volatile and provide only one line of information at a time. On the other hand, it is highly desirable for many purposes to have a printed readout of the entire series of calculations performed. The hard copy printed readout would allow the operator to check the inputs that were placed into the calculator and would also allow copies to be made of the calculations performed or to retain copies of records for business purposes.
Some of the larger and more expensive electronic business machines do provide a printed readout in addition to the volatile display. Some of these machines employ standard printing drum techniques to produce a printed readout, while others employ thermal printing techniques to provide a printed readout. Thermal printing techniques involve non-impact printing wherein specially treated paper is placed in contact with a thermal printing station having an array of heating elements, such as, nichrome resistors, which are selectively energized and heated so as to print a line of characters on the specially treated paper.
However, most of the existing mechanisms for advancing paper past the printing station are quite complex and expensive. Such existing mechanisms also require a number of time consuming manipulations to insert the paper within the paper feeding mechanism before the electronic business machine is ready for operation. In addition, such mechanisms generally advance paper from a roll of paper. In view of the latest packaging techniques, wherein electronic business machines have become quite compact, a roll of paper is relatively large and bulky in comparison.